[R-390] Fwd: New list member here

[bavarianradio at comcast.net]

Hi John, Welcome to the list!! Congrats on the "A" . I have a spare power supply here if you want to buy some 26z5's and restore it to original.  Good Luck!! I'm just starting (tonight) a strip down restoration of a BC-779.  I hope to see you soon (Nearfest?) 73's Ross W1EKG

----- Original Message -----
Hi, I go by either John or JP; my call letters are N5CQU.
I picked up my first R-390A recently, and have started to tear into it.  It
seems to be a Franken-radio; I'm not sure I have two modules from any given
manufacturer.
First up were the filter killer and rotting caps.  Those are done.  The big
electrolytics on the Audio Chassis test good.
I am now tearing into the power supply, which has the 1N561's.  The tube
sockets have been pushed in and filled with what looks like an RTV.  I do
not like the condition of the wiring - it looks like many connections had
enamel wiring or tinned bus.  There is corrosion evident, enamel almost
looks melted off, and the solder looks filthy.  There are some signs of
crystallization on the aluminum bracket, too.  I have been wondering
whether the acid that is present in an RTV cure was working some chemical
reactions over time.  The teflon wiring looks pretty good, however, and the
transformer has the appropriate voltages.  The diode cases are showing
signs of rust, which is a first for me.  The module was made by Motorola.
So, anyway, I'm taking it apart for washing and bus wire / diode
replacement.
Then onto the next module - probably the audio.  The audio has an
interesting oily film all over everything, but I have not determined what
leaked yet.
My thanks to the many people who have posted to the list over the years,
and to the people who have collected "The Pearls."  All of you are giving
me a heck of a hand up the learning curve.
73 de N5CQU
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